In a number of situations arising in many settings, it is desirable to separate mixtures of materials. For example, it is often desirable to remove particles from a liquid “contaminated” with such particles. For example, in the machining industry coolant liquid becomes contaminated with metal particles. Such particles can be separated using filter media elements such as filter bags, baskets and cartridges which separate by size exclusion.
As illustrated in FIGS. 1A through 1C, a number of currently available separation systems represented by system 10, include a separation media element/bag 20 supported by a screened basket-shaped support 30. In general, current practice in such systems is to rely on a metal or plastic ring 22 on the top perimeter of filter bag 20 to seal itself to the sidewall of a generally cylindrical filter housing 12. Filter housing 12 is closed at a top portion thereof by a lid 14. In the embodiment of FIGS. 1A and 1B, sealing ring 22 rests upon a radially outward extending flange 32 formed around the upper perimeter of support 30. Variation in any number of variables, including, but not limited to, filter housing diameter and/or roundness, fabric thickness, sewing technique, and ring diameter and/or roundness, can cause significant bypass of dirty fluid around filter seal element 22, causing particles many times larger than the filter media rating to pass through filter element 20 and out of filter housing 12.
Some separations systems have used O-ring type seals in an attempt to limit leakage of fluid to be filtered around a filter element with limited success. See, for example, U.S. Pat. No. 5,462,678, in which an O-ring is used to form a seal between an outer sieve basket and an inner wall of a separation system housing. Indeed, although there has long been a need to decrease the amount of such leakage, currently available separation systems have been unable to satisfy that need.
It is desirable to develop improved devices, systems and methods that reduce or eliminate the above-identified and other problems associated with currently available separation systems.